1. Field of the Invention
The present invention relates to a phase calculation apparatus, and more particularly to, an apparatus for calculating a phase corresponding to I/Q data components which are signals received during wireless/wired communication.
2. Description of the Related Art
Signals transmitted during wireless/wired communication include I/Q component data. Frequency deviation occurs due to a difference between carrier frequencies between a reception side and a transmission side. The frequency deviation may greatly influence the restoration of data received according to a modulation type. The received data can be properly restored only if the frequency deviation is compensated for in types of communication such as orthogonal frequency division multiplexing (OFDM) or wideband code division multiplexing access (CDMA). In order to compensate for the frequency deviation, the reception side must estimate the frequency deviation by detecting a phase of an input complex signal during a specific signal period, e.g., a preamble period. Therefore, the phase needs to be accurately detected in order to increase frequency deviation compensation performance. In order to estimate the frequency deviation, the phase of the input complex signal, i.e., the I/Q component data, needs to be calculated. A conventional phase calculation method uses a memory or lookup table as a value of arctan (the I/Q component data) if the input complex signal includes the I/Q component data. However, the conventional phase calculation method must store phase values of I/Q data component data values having the same phase values in the memory, which causes unnecessary memory use, and must also store the number of bits of the I/Q data component data values to be determined according to the accuracy of the phase calculation.